Sound recording device



March 21, 1933. M H, PAGE 1,902,290

SOUND RECORDING DEVICE Filed NOV. 19, 1929 Parentalv Mar.. .21, 1,933 td 1,9025290 uNrrED s'rxresv PATENT; OFFICE MILTON HARRISON PAGE'OFCOHOES, NEW YORK soUND RECORDING DEVICE ,Application leil November 19,1929. Serial No. 408,393.

The present invention relates to a device Referring to the drawing inwhich is shown for recording sound waves, and more particua preferredembodiment of the invention: larly to improved means for varying the am-Figure 1 is a side view of a recorder showplitude orlarea of a beam oflight in response ing my invention applied thereto. 5 to variations in avibratory member and re- Figure 2 is a sectional view substantially 55cording the modulated light on a sensitized along the line 2-2 ofFigure 1. lm, strip or the like. Figure 3 is an enlarged detail viewy ofthe An essential object of the invention is to vibrating member anditsassociated parts. provide a vibratingmember for cutting oi Figure 4 is aside elevation of a modified l0 a beam of light projected on a movablephotoform of the invention with parts in section. 60 sensitive lm, saidvibrating member being Referring to the drawing in which like nuoperableby the sound to be recorded and armerals indicate like parts in theseveral views, ranged to form'on the iilm transverse images 10 denotesan 0pt1cal system arranged to or undulations that represent the characpIOJect a beam of light 11 onto the track por- 15 ters of tho Sound to borecorded, tion 12 of a sensitized lm 1 3 for the purpose 65 A furtherobject consists in a new and .im- 0f reCOrdlIlg sound thereon. L provedmethod of recording sound waves on A member 14 which is operativelyaSSOC.- asonstized frlrn or tho like, ated with a suitable device, notshown, for A further object Consists in providing a collecting thesound'to be produced, has con- 20* Substantially tapered vorwedge-shaped vinected Vthereto as at 15 a substantially L- brating'member of less width than the pro- Shaped arm 16,-,th`e vertical portionof which jeoting beam of lightso as, to produoo marterminates in avlbrating shutter 17 arranged ginal dark bands adjacent the edges of thet9 13 IIlOVed Into the path of the beam of sound track portion ofthefilm and coexlght 1 1bythe member 14. 25 tensive with the lengththereof, which bands 0 ObVlOllSly, the Shutter 17 and its Connec- 75prevent overshooting of the recording lines tlOIl t0 the member 14 mayassume various and not as a, base for the Sound track portion other.forms so as tobe projected into the path of the film, of a beam oflight to record on a sensitized. Another object is to provide means forfllm, the modulated light when the vibrating 30 producing Sound Waves ona film, which member *is brought into operation. 80

- waves are sharply dened so that the pro- The 111111113 iS led from aguide roller 18 duced sounds will be clear and distinct; the 219111161 adrum 19 111 Such a manner as to recorded lines being formed in such amanb1` 11g thesolmd tck Portion 11g-*111m OCal ner as to addamplitudefto the recording and allgnmellt Wlth the projected beam oflight materially eliminate g1'0undn0jses j I'OID the Opl'llcal SyStT 10.T116 A still further object is to providea sound .PaS'SeS rQm i119 IOWGIpOltiOn 0f the drum recorded film withmarginal base bands or 19 aIOlHld3f gulde 1'01161 20 and `is carried t lines and transverse images orundulating re- OVel' t0 il 101181 2.1 IOm Where it may be concordedbands that extend inwardly from both dllCted t0 any Sllltble pOiI'lt forWinding.

o sides of the track portion of the film and form The film 13 aS il? iSadvanced toward the .90

an .intermediate blank area, the Width of' optical system 10 has thetrack portion 12 the recording images in their direction of thereofblank and aS 1 P2SSS the, beam f movement representing thecharacteristics of llght 11, the member 11 1S. actuated to cause theSound recorded yand the length of the the shutter 17 to be moved 1naccordance with '-4 images indicating the amplitude for area, of. thevibrations set up by the sound to be re- 95 the vibrations. Y corded,and transfer the images formed by Other objects of the invention willbecome the modulated light onto .the 'sound track apparent from' thefollowing description :portion.12. 5 -when taken in conjunction with theaccom- In order to accurately and clearly record l panying claims anddrawing. the natural characteristics ofthe sound vibra- 10 recorder,ythe shutter 17 whenin its lower` most position will not completely cut0E the light, but willallow portions thereof to be projected on the filmso as to produce the dark bands 22 and 23 of constant or uniform width(Fig. 3) along the outer edges of the track portion 12, which bandsextend lengthwise of' thelm and act as a base for preventing thetransverse vibrations of light recorded on the sound track portion fromextending beyond the edges thereof.

It will be seen that in the operation of the device the vibratingshutter 17 causes the record to be produced on the sound track .portionin the form of transverse undulations or stiriations 24 and 25, whichextend in staggered relation from the sides of the .sound track.portion. The width of the recorded images or vibrations 24 and 25 .intheir direction of movement designatingthe char- "lengthwise l film tomodulate thelight before it reachesA acteristics of the sound, jWhilethe length of the images represent the amplitude of vibratlon.

The adjacent sideso'f 'the images 24 and 25 are spaced from eachother bya medial blank portion 26 which varies in width in accordance with thevibrations imparted to the shutter 17.

As shown in Figure 3, the .lower portion of the film indicates how thedark bands 22 and 23 are formed when the shutter 17 is maintained'in itslowermost position relative to the optical system 10.

In the modified form of the invention illustrated in Figure 4, means areprovided for interrupting the light-within the optical system and thenprojecting the modulated light onto the track portion of the film in themanner as previously described. In this form of the invention, theoptical system 27 has mountedtherein a partition member 28 havingl anaperture or slit 29 through which the concentrated beam of light passesand is interrupted by the vibrating shutter 30 connected f to the member31 as at 32.` The shutter 30 is of less width than the opening 29 so asto form the bands 22 and 23 along the marginal leo sides of the trackportion of the film While the member 31 is suitably connected to thesound to be recorded s'o asto cause the actuation ofthe shutter 30 inresponse thereto.

It is to be understood that the form of the invention shown anddescribed is merely illustrative` of preferred embodiments and that suchchanges may be made as fall withinthe purview of one skilled in the artwithout departingt'rom the spirit of the invention and thejscope'of'theappended claims.

and having a shutter arranged to be moved .edges thereof.

Leoaaec l. The method of recording sound Waves on the track portion of asensitized lilm, which consists in projecting a beam of light onto thefilm and modulating the amplitude of an intermediate portion of thelight longitu'dinally ofthe sound track before it strikes the film inaccordance with the variationslin the sound waves'so as to produceadjacent the sides of the sound track dark lines of uniform width thatextend lengthwise of the film,

preventing the extending beand transverse undulations extending inwardlyfrom said lines, each of said having a substantially wedge-.shapedvshutter arranged to be moved into the path of light of the sound trackportion of the the lm, said shutter being of less width than the beam oflight so as to form definitely delined .bands of uniform opposite sidesof the sound track portion of the film, and transverse images extendinginwardly from said bands, each of said bands acting as a base forpreventing the transverse images from extending beyond the edgesthereof.

3. A sound recording device comprising an opticalfsystem, a sensitizedfilm, means for moving the sound track portion of. the film past saidoptical system, a vibrating member operable by the sound waves to berecorded, and having a shutter provided with downwardly extendingconverging sides and arranged to be moved into the path of light beforeit strikes the film to modulate the light, said shutter being of lesswidth than the beam of light so as to provide spaced bands of uniformwidth which extend lengthwise of the lm adjacent the outer sides of thesound track portion, and transverse images extendinginwardly from-saidbands, each of lsaid bands acting as a base for preventing thetransverse images from extending beyond the 4. A sound recording opticalsystem, a sensitized film, means for moving the sound track portion ofthe film lpast said optical system,a vibrating member operable by thesound waves to be recorded,

into the path of light before it strikes the lm so as to modulate thesame, said shutter being of substantially wedge-shape and of less widththan the beam of light so as to produce adjacent the sides of the soundtrack dark bands of uniform width that extend width adjacent the devicecomprising an i' iso - lengthwise of the lm, and transverse undulationsextending inwardly from said bands, each of said bands acting as a basefor preventing the transverse undulations from ex- 5 tending beyond theedges thereof.

In testimony whereof I' haveV hereunto set my hand.

so j

MILTON HARRISON PAGE.

